In the fields of freight rail, commuter rail, light rail, and heavy rail, it is important for a lookout, flagger, watchman or advance watchman to know the safe distance the flagger needs to be away from a work zone, work crews, or on track equipment. The flagger must safely alert work crews or railroad personnel on the tracks of an oncoming train or rail vehicle. Flaggers often rely on counting structures, which may result in an inaccurate distance from the work zone. In many instances, the counting method may result in the flagger being too far away from the work zone for workers to hear a warning.
Because working on rail tracks can involve activities such as digging, hammering, and other actions that produce loud noises, workers frequently cannot hear or see a flagger's alarm or visual warning of oncoming trains, and, consequently, may be in great danger of being struck by an on oncoming train. One current warning method employs flag men or whistle men who are positioned a distance away from the workers, such as 2,000 ft., 3,000 ft., or a distance related to the stopping distance of a train from a work crew, in both directions of the track. Such flag or whistle men signal with their flags and/or their whistles to warn of oncoming trains. Due to lack of worker attention or distracting ambient noise, work crews sometimes do not see the flag waving or hear the whistle blowing, and thus such conventional warning methods can be unreliable. In addition, previous and current methods do not provide a visual distance or alert to a train or on track equipment operator, or provide the train operator specific information regarding the type of railroad personnel ahead on or near the track. Further, previous and current methods do not provide early alert to track walkers, track work gangs, and track inspectors that a train is approaching.